Sound recording and reproducing



Sept. 29, 1942. y B. A. PRocToR ET Al. I 2,296,870

SOUND RECORDING AND REPRODUCING l5 Sheets-Sheet 2 Filed July 8, 1958ATTORNEYS Sept. 29, 1942. B. A. PRocToR ET AL, 2,296,870

SOUND RECORDING AND REPRODUCING Filed July 8, 1958 l5 Sheets-Sheet 5 .LOd@ E T m N d. wwf m www M mc Pd Am mm mm E@ l vl Sept; 29, 1942.

B. A. PROCTOR ET AL SOUND RECORDING AND REPRODUCING Filed July 8, 193815 Sheets-Sheet 5 IN VENTORS Buffa/1 Afroc for and Fwd/'nana' C. WThiede BY' Oka-cav VL W/ ATTORNEYS sept. 29, 1942. "B, A. PRQcwR Em.2,296,876y

SOUND RECORDING AND REPRODUCING Filed July 8. 1938 l l 15 Sheets-Sheet 6ATTORNEYS Sept., 29, 1942.

B. A. PROCTOR ET AL.

SOUND RECORDING AND REPRODUGING Filed July 8, 1958 l'sneetS-sheet fr 5V@may 1- ATTORNEY5 Sept., 29, w42.. a. A.PRocToR ET AL 2,296,87@

SOUND RECORDING AND REPRODUCING Filed July 8. 1938 15 Sl'xeebs-f-Sheec.-8

m m Ode m@ m VWM w Nf ICW A 0 WC w Q .d ll A mm fw a 5f Vl B Slept. 29,1942. B. A. PRocToR ET AL 2,296,870

SOUND RECORDING AND REPRODUCING Filed July s, 1958 15 sheets-sheet 5ATTORNEYS Sept` 29, 1942 B. A. PRocToR ET AL 2,296,870

SOUND RECORDING AND REPRODUCING Filed July 8, 1938 l5 Sheets-Sheet lO Il I l 1 l I l l ffy/1 INVENTORS Ear-fan AProco/i and Ferm/fand C WTh/ede 'y HY ATTORNEYS B. A. PROCTOR ET AL.

SOUND RECORDING AND REPRODUCING ATTORNEYS Sept. 29, m42., A BAA.PRoc'roR ET AL. 2396,37@

SOUND RECORDING AND REPRODUCING Filed July 8, 1958 15 Sheets-Sheet l2 BY@ma .9L/lu@ ATTORNEYS Sept 29, 1942- B. A. PROCTOR ET AL SOUND RECORDINGAND REPRODUCING Filed July 8, 1938 15 Sheets-Sheet 13 www@ ATTORNEYSSept. 29, 1942. B. A. PRoc'roR ET AL 2,296,870

SOUND RECORDING AND REPRODUCIG I Filed July 8, 1938 v l5 Sheets-Sheet 14l y I I Z Y H424. 6E Il, j

5f/l 95 w f Barron A. Proggy 59115 ferd//M/d C W Thiede 5) "urgaa Yl` vATTORNEYS SePt- 29 1942- B. A. PRocToR ET AL 2,296,870

souND RECORDING AND REPRODUGING Filed July 8, 1958 l5 Sheets-Sheet 15Patented Sept. 29, 1942 l SOUND RECORDING AND REIRODUCING Barton A.Proctor, Larchmont, and Ferdinand C. W. Thiede, Hempstead, N.Y.,aassignors to B. A. Proctor Company, Inc.. New York, N. .Y., acorporation of New York Application July 8, 1938, Serial No. 218,082

\-' 30 Claims.

This invention relates broadly to sound recording and reproducing, andmore particularly to machines and records adapted to be used in officework for the dictation and transcription of'letters, memoranda, etc. Theinvention involves various features of special utility for dictationpurposes, and also many features of more general application.

In accordance with prior commerical practice,

dictation machines are designed to be used with cylindrical wax records.l,These records are expensive,. bulky and fragile. that the records bere-used, and hence it is necessary to provide a shaving machine forshaving the transcribed records to prepare them for reuse. This involvesan added investment for equipment, consumes the time of the operator forperforming the shaving operation, and puts an end to any furtherpossibility of$reference to the shaved record for verification purposes.Valuable oilice space is consumed by rebords waiting to be shaved.

It is not feasible to keep any substantial number of unshaved records onhand for reference, both because that would involve an inordinateinvestment in records, and because of space requirements for storing therecords. The records must be handled very carefully at all times becausethey are extremely frangible. The dropping of a blank or transcribedrecord involves destruction of the record, but the dropping of anuntranscribed record is likely to be much more serious because of theloss of the material recorded upon it.

Important objects of the present invention have to do with theovercoming ofthe above mentioned drawbacks by providing an improvedrecord which is small in bulk, infrangible, and so inexpensive that itmay be lfiled away, if' desired, after it has been transcribed, and maybe eventually discarded without re-use; and by providing a recording andreproducing machine capable of use with the improved record in a highlyeicient and satisfactory manner.

' The improved record is desirably in the form of a through-deform-abledisc of tough, flexible material, adapted to have a sound record scribedupon,it, and of no greater thickness than an ordinary sheet of letterpaper. Such -a record has clear advantages of cheapness, small bulk, andinfrangibility, but presents serious problems in the matter of its usefor recording and reproducing purposes. l

The illustrative, through-deformable record becomes indented through bythe formation of Economy demands K the sound record groove, and tends tocurl. When simply spread out flat it has no substantial rigidity,atleast no rigidity suflicient properly to transmit an adequate andpositive drlv ing force to the cutting point. The record also presentsdifliculties in the matter of securing a properly cut sound record, bothbecause of its tendency to transmit machine noises and vibrations intothe record track, and because of its tendency to impose upon the recordjtrack grain pattern characteristics of any solid backing or platen thatmay be opposed to .the stylus. The' generation of background noises atreproducing also presents a diiiiculty. the present invention have to dowith the overcoming of these diiculties.

Briefly, the illustrative machine desir-ably inlcludes a mountingspindle, upon which a thin,

flexible disc record may be impaled, and opposed feed rollers spacedfrom'the spindle for engaginga opposite faces of the record and drivingthe record about the spindle axis. The spindle is mounted upon acarriage, and is connected to drive a. feed screw, which is also mountedupon the carriage. Rotation of the record is transmitted to the spindleand thence to the feed screw. The feed screw cooperates with an axiallyimmovable half-nut, which is adapted to be engaged with and disengagedfrom the feed screw at will. When the half-nut is engaged with the feedscrew the carriage is caused to be moved axially of the feed screw andto move the record spindle away 'from the record driving rollers, sothat that zone of the record which ex` tends radially between thespindle and the record driving rollers -is maintained constantly undertension during the driving of the record.

A stationary stylus is mounted to act upon the record in the tensionedradial'zone of the record whichextends between the spindle and the pointof contact of the record with the driving rollers, and closely adjacentto the latter point. The fact that the stylus acts upon a portion of therecord which is constantly under tension is a very important one inconnection with the control of the record and also with Importantobjects of f points of view.

support, and cooperating guides are provided for maintaining the recordin substantial conformity with the curved support. This marmer ofsupporting the record is importantI from many from a point starting nearthe center and is caused to progress outward toward the circumference ofthe record. As the groove progresses the record becomes indentedthrough, and these indentations constitute a multiplicity of i'lnecorrugations which are disposed crosswise of the radius of the recordwhich join the axis of the spindle with the point of engagement of thefeed roller, and which are bent' downward at opposite sides of suchradius. The maintaining of the record thus bent, together Withthe factthat these fine corrugations are present, causes the radial zone of therecord engaged by the spindle, the stylus, and the feed rollers to bequite rigid. This is a very important point in connection withthesecurement of a firm and adequate driving of the record past thestylus.

'I'he spiral record groove is cut.

The curved support has the further advantage that it acts as a brakeupon the record. When the driving rollers are separated, the record andthe parts driven by it, which are all of very slight mass, are caused tocome instantly to rest. The curved support for the record has thefurther advantage that one horizontal dimension of the machine may beconsiderably shorter than the diameter o a record.

The curved support also takes the curl out of the record and causes allportions of the record to be controlled in an orderly manner at alltimes.

The fact that the record and the parts which rotate in uniform relationto the record have relatively slight mass and slight inertia has animportant bearing on the accurate production of the desired variablerotary speed of the record, regardless of whether the record is startedand stopped from time to time.` The uniformly running motor and therelatively massive parts which run in uniform relationto the motor arenot perceptibly influenced by the gradual and slight change of loadwhich results from the progressive change in rotary speed of the record.From this point of view it is an important point that the need for aturntable is obviated. The obviation of a turntable is also veryimportant from. the standpoint of securing instantaneous stopping of therecord and instantaneous acceleration of the record to 'the desiredspeed after a stop.

The recording operation does not start at the very center ofthe recordbut at a substantial distance outward from the center. 'I'he centralportion of the record is without indentations and, therefore, withoutstiiening corrugations. It is a feature of the invention, however, thatthis" central area of the record has aftixed to it a label which bothaffords a. writing medium for receiving notes relative to the materialrecorded, and a reinforcement for the central area of the record tomaintain that area dat and substantially more .rigid than thesurrounding area. Prior practice has involved the provision of `aseparate, loose memorandum slip for association with each record, but noprovision has been made for assuring the -maintenance of suchassociation. No claim is rnade herein to the record, per se, the recordbeing claimed in continuation in part applications of Barton A. Proctor,Serial No. 438,713, filed April 13, 1942, for Records for recordingandreproducing sound, and Serial No.

436,243, led March 26, 1942, for Records for recording and reproducingsound.

' The machine further embodies means for keeping out of the sound trackextraneous noises, such as scratch noises, background noises, and noisesoriginating from the vibration of various machine parts. It is notpossible to produce a satisfactory sound groove in a. thin, plasticmaterial supported directly on a hard metal surface without developingbackground noise in the record caused by the grain pattern of thematerial of which the supporting base is made. In order to avoid such aresult the machine of the present invention is made to include a platenin the form of a resilient cushion for engaging the back of the recordmaterial.

It is a further feature of the invention in accordance with anadvantageous form thereof that not even the resilient platen is directlyopposed to the stylus, but that the stylus is rather caused to engagethe record material under tension with the record held in bridgingrelation to supporting points of the platen.

In reproduction it is important that the record material, at the pointof contact with the reproducing stylus, be not allowed to run infrictional engagement with any underlying material because such frictionwill inevitably introduce objectionable noises into the `reprcducerpickup.

Such defective operation'is"'avoided-in the machine of the presentinvention by making the platen free to roll in contact with the recordmaterial.

The machine desirably involves both electrical recording and electricalreproducing, separate styluses being used for the two purposes, andseparate circuits being established, according to whether recording orreproducing is in progress. It is a. feature of the invention thatmechanism is provided under the control of a single' operand' 'becauseof the delicate and accurate responsiveness tothe reproducing styluswhich may be secured.

In accordance with still another featureA of the invention, provision ismade in the electrical part of the machine of an overload protectivedevice for limiting the amplitude of the electrical vibrations, andhence of the reproduced sound. This device desirably consists of a glowtube connected inductively to the input of the recorder circuit and tothe output of the reproducing circuit. A circuit including such a tubehas the characteristic that it will absorb no energy from the primary orinput circuit with which it is inductively coupled unless and until theconditions of the primary circuit are such as to induce a potential inexcess of a denite value. When such deiinite value is exceeded, however,the tube will glow, and the circuit will substantially modify thecurrent owing in the primary circuit with which the glow tube circuit iscoupled.

No claim Iis made herein to the recording and reproducing units and theelectrical apparatus combined and associated therewith because thatsubject-matter is claimed in our continuation in 2,296,870 Y 3 partapplication Serial No. 436,244fled March trical connections between thevarious parte of 26, 1942, for Sound recording andreprodilcing; themachine.

A further advantageous feature residesin the Referring to Figs. l to 4,there is provided a fact that the machine embodies a record storagecasing in which the component parts of the decompartment. Thiscompartment desirably exvice are suitably mounted and supported, saidtends along the front and bottom of the main casing. comprising a rearwall, 53, base 54, a` front frame of the machine,` arid is rather thin.It is wall 55-which is shorter than thev rear wall, a top capable,however, of holding a very substantial wal1'56 having a dependingportion 51, and end number of thin, flexible disc records, and therecwalls 58 and 59. The top wall extends downords, because of theirflexibility, can be very wardly as shown at B0 in Fig. l to provide aflat readily caused to follow the, curvature 'of the -surface 1I at alower level to accommodate cercompartment as they are introduced into itor tain controls tobedescribed later. Also asshown withdrawn from it. l.lin Figs. 1 and 2 the end wall 58 is lower than end It is a furtherfeature @that provision is made wall 59 and at its top level a narrowshelf or of a retractible reference scale, cooperative with bracket 6I,secured to the rear wall 53, extends the" record spindle for indicatingto the user of horizontally to provide a support for the hinge themachine the points on the record at which block 62 secured thereto byscrews 83. A frame 64,

j arrows;

' the line Ill-I8 of Fig. 4;

`view of the machine;

various matters are recorded. having the-spaced apart parallel arms 85to the Other objects and advantages will hereinafter outer ends of whicha graduated scale 88 is beappear. 4 20. cured, is hinged to block 62 bythe pivoted sup-- Fig. 1 is a front elevation'ofthe machine; ports 61.For the purpose .of supporting the Fig. 2 is atop plan viewof themachine; scale when it is moved back on its hinge in order Fig. 3 isaside elevation as view from the left to insert a record, a rearwardlyextending suphand end of Fig. l; port arm 68 is secured to frame 6I, itslower end Fig. 4 is a vertical side view insection, the- 25 being bentover to PrOVide RSUDPOI 09 which enon the line 4-4 of Fig. 8; gages andrests on the -block 62v when the scale is Fig. 5 is a perspective viewof a cam unit which thrown back. It will be obvious from Fig: 2 that.effects the setting of the reproducer and the rewhen the scale is thrownback, a large open area eerder; is presented at the top of the casingfor the Fig. 6 is a side elevation as seen from the right 30v insertionof a thin, flexible record 10. to be later hand side of Fig. 1,\with theright hand end plate described. Also as .shown in Fis. 2,`the natporremoved;

Fig. 7 is a sectional side view taken on the line Shown at 'l2 andterminates at 13 so as to leave 1--1 of Fig. 8 and looking in thedirection of the aispace between it and the front wall 55. This spaceforms part of an opening or slot .14 ex- Fig. 8 is a sectional frontview taken on the tending across the front 0f the Casing and 91'0-Illnes 8-8 of Fig. 6; i vided as a storage place for usedor unused rec-Fig. 9 is a view similar to Fig. 8 with some of ords. The extendedportion 12 of the casing tOD the parts removed and showing the carriageinv also has a slot 18 through which a switch handle a differentposition; 40 15 of an on-oi switch 2 (see Fig. 25) extends, Fig, 10 isa, sectional top plan view taken en and also accommodates a volumecontrol knob 50. Theopening 14 extends between the corner posts Fig. l1is a fragmentary, sectional, top plan .'11 Which engaged the end' platesand $10118 the length of thisopening the front wall and base areconnected by a thin concave strip 18 which serves to guide the record asit is inserted for storage.

figure being taken Fig. 12 ,is a vertical section taken on the linel2-i2 of Fig. 18;

Figs. 13 and 14 are detail front views in sectiony The vertical portionofthe storage space is dcshowing the relative positions between therefined at the rear by an upright wall-.J9 which is producer arm and thelifting arm therefor; convexly curved near its lower end opposite theFig. 15 is a fragmentary top plan view in sec- 50 strip 18 and issecured to the front of a wide horticn, taken on thence ls-ls of Fig.16,.,showing izontal member 80 which supports the electric thereproducer and the recorder and their shiftmotor 40 and other parts ofthe driving mechaing mechanisms; nism, the supporting member 80extending to Fig. 16 is a sectional side view taken on the rear wall53.v As shown more clearly in Fig. 8. line lS--I 6 of Fig. 15 andlooking in the direction 55 member 80 is secured to and supported by agenef 'the arrows; erally rectangular shaped bar 8| which extends Figs.17 and 18 are views similar to Figs. 15 and across the other end. Thelarger parts of the end 16 respectively but show the renroducer in itsplates 53 and 59 0f the casing are perforated active position, thesection of Fig. 17 being taken with holes 83 so as to Permit Circulationof air on the line i1l1 of Fig. 18; 60 and dissipation of the heatgenerated in the mo- Fig. 19 is a view similar to Fig. 18 but shows the1501' and amplifierunit to be described later. parts shifted to renderthe recorder eiective; These perforated end plates are milde SeparateFig. 20 is a fragmentary sectional side view,l of from the main bodyportion of the casing and the right hand end of Fig. 6, showing the'parts are secured in position by screws 84 and 85. In

, tion 1l of the top of the casing is extended as shifted to theireffective positions; inserting a record in the vertical portion of theFig. 21 is a detailed front view in section of slot or storage space 1Iwhen its edge meets the the record platen roller; COIICRVB Strip 73 itslides along 'this strip and is Fig. 22 is a section view of a fragmentof the guided into the horizontal portion 86 cf the open roller shown inFig. 21; and a portion of the space between the flat support 80 and thebotrecord bearing thereon; f 70 tom casing wall 54. Fan blades 81.areprefer- Fig. 23 is a top plan view of the record; ably secured to themotor shaft to create a cir- Fig. 24 is a sectional detailed view of themeans culation or current of air through the casing. whereby the recordis held connected to the As shown more clearly 'in Fig. 4, a curvedsheet` spindle; and of thin metal 88 formed into the shape of a Fig. 25is a circuit diagram showing the elec- '.'5 transverse section of aturtle back is provided to properly support the record 10 from below.the

' under surface of the record, frictionally engaging member 08 as therecord rotates. 'I'he turtle back is supported at vthe front by itslower edge resting on the curved portion of strip 10, a

spacing `member 89 serving to hold these memalong its top is providedwith a slot 94 (see Fig.'

2) to permit the passage of the record spindle 95 therethrough. Abracket 91 secured to the inner surface of wall 19 and extending alongthe top thereof serves to partially conceal the front p0rtion of recordsupport 88, its curved rear surface 06 being spaced from 88 to provideproper clearance space. f

RECORD DRIVE Referring to Figs. 6, 8, and 11, the shaft 98a of motor 40is provided with a pulley 98 over which passes belt 99 engaging pulley|00- secured near the end of a shaft |0| carrying a friction drive wheelor feed roller |02 at its inner end, the latter wheel directly engagingthe lower face of the record to cause its`rotation. A partition wall |03extends across the casing near one end and having a slot 03a thereinthroughl which shaft |0| passes freely, this shaft being journaled in apair of spaced apart bearing lugs |04 extending from a stationarysupporting bracket |05 which has parallel end Walls |05 and |01extending toward therear of the easing, end wall |06 lying alongpartition wall |03 and wall |01 having an aperture |08 to permit freepassage of a rod |09 forming part of the record carriage |09a. As shownin Fig. 7, bracket ported by the oppositely disposed channel bars ||0and the spear bar l||0a. A pair' of guide members or rods 5| and 52(Fig. 8) are provided to guide the record carriage, one end of rod 6|being supported in the end wall |06 and its other end in an arm I la ofa bracket located near the end of the casing. 'I'he outer end of rod 52is supported by bracket ||I and its inner end by bracket |05.

The record carriage comprises a frame H2 secured to the left end of thehollow rod |09 and a depending arm ||3 secured at its right hand end, ashaft ||4 being journalled .in frame ||2 and arm ||3 and being threadedfor that portion of its length between these members. shown in Fig. 4,rod 52 passes through a notch i |2a in the lower end of frame H2 and rod5| through a bore near its top whereby the frame is supported andguided, rod 5| also passing through a bore in arm ||3 near its top tosupport and guide it. Frame 2 in its hollow portion houses a gear 6secured to shaft or screw `||4, gear ||6 engaginga skew gear ||1 securedto the record spindle 95. Frame ||`2 is provided at one.end with twoprojecting bosses ||8` to which the ends of a, transversely extendingthrust member 9 are secured by screws |20. The end of threaded screwshaft ||4 is slightly bored to receive a steel cball |2| which alsoabuts against member ||9 so that the endwise motion of shaft |I4 istransmitted through the ball to |05 is suprear wall 53. 'I'he shaft therecord carriage. In order to cause endwise motion of the screw shaft ||4upon its rotation by the record spindle and gears ||5 and described, anarm |22 is secured to a shaft |23 which may' be rotated slightly bymeans to be described later, the end of the arm being provided with athreaded portion |24 which may be brought into engagement with thethreads on shaft ||4. .When so engaged, arm |22 serves as a stationarynut, causing endwise motion of shaft H4. A coil spring |24a secured tothe end of the arm and to a stationary pin |25 biases the arm towardsengagement with the shaft ||4 (see Fig. 7). A short slot |26 (Figs. 7and 8) is provided in record support 88 through which friction wheel |02extends slightly in order to engage the record.

Referring now particularly to Figs. '7, 8 and 11, a frame |26 ispivotally mounted on a shaft |21 and comprises a cross bar |2811r havingspaced apart lugs |28 in which is journalled a shaft |20 which carriesat its end a friction wheel |38 mounted to engage the upper surface ofthe record 10 directly over wheel |02. 'I'his shaft is driven by afriction wheel |30', arranged to engage the hub portion i0|' of pulley|00, the peripheral portions of wheels |02, |30 and |30' preferablybeing formed of rubber. An arm 3| bent as shown in Fig. Il is secured tobar |28a of frame |26, a coil spring |32 having one end secured to thearm and its other end to a pin |33 carried by a bracket |34 attached tothe rear wall of the casing. When it is not desired to drive a record,the parts are in the position shown in Fig. 7 with wheel 30 elevatedabove the record, and wheel |30' not engaging driving hub- |00'.As-shown, a vertical arm |35 is secured to a shaft 35a carrying a gear|36 which meshes with gear |31 secured toV a vertical shaft |38supported by a bracket |34, secured to the |38 passes through the topportion 1| of the casing where it is pro-` vided with an operatinghandle |39. When the handle is inthe neutral position shown in Figs. l,2 and 7, arm |35 serves to hold wheel |30 elevated so that the record isnot driven; when handle |39 is moved either toward the right to recordor to the left to reproduce, arm |35 moves up, as in Fig. 20, to allowspring |32 to depress and hold the wheel |30 in engagement with hub |00'and wheel |30 record which is then driven by the wheels |02 and |30. f

To provide a ready means for the operator to stop a record at any timeindependently of the handle |39,van upstanding arm |40 is secured to thebar |28a of the frame |26 and adapted for engagement by a head |4| (Fig.7) secured to the end of a exible-Bowden wire |42 which is enclosed bythe usual nexible casing |42'. A bracket |43 projected from the innerwall of the casing serves to support one end of the wire |42. The otherend of the wire is attached to a. plunger |44 terminating in a knob |45,the plunger being slidable in a casing |46 having a hand or nger grip|41 and a bayonet slot |48. A compression spring |49 engaging the endwall of casing |46 and the end of plunger |44 biases the Bowden wire toits outer position, permitting wheel |38 to engage the record. To stopthe record, it is only necessary for the operator to press knob |45which will cause the head 4| to push arm |40 backwards, thereby raisingidler wheel |30. The bayonet slot |46 is provided in the casing in whicha pin |5| may be advanced and in rm engagement with'the asaeasvoslightly rotated, when the operator desires to. elevate wheel |30 for anextended time."

Record and its attachment .machine as heretofore described. Before use,

both faces of the record are smooth, the sound track being formed as therecording is made and causing the record to become distortedor wrin-`kled so that it is no longer fiat.

We have found by experiment that a slight coating of high melting pointwax, which is applied to the surface of the record in a solution ofcarbontetrachloride which dries very rapidly, is desirable and acts as astylus lubricant in the operation of drawing the groove in the recordmaterial. Alternatively, a coating formed of ethylcellulose and' wax maybe employed with the added advantage that the wax does not read-- ilyrub off and the heat developed in the process of recording serves toliberate the wax lubricant.

A disc of paper |52 is cemented to the upper face of the record at itscenter, this disc permitting notations to be written upon it for giv.ing .the positions of various matters recorded on a. record. The discalso serves to reinforce the record at the region where it is attachedto the spindle. As shown, an aperture is formed through both the labeland record having a plurality of inwardly directed projections |53resembling gear`teeth.

Record spindle 95 is formed with a circular shoulder or flange |54 upon-which the center of the record rests. Just above this, a series offlutes |55 is formed into which the projections |53 on the record extendto thereby effectively transmit the rotation of a record to spindle 96.

-A hollow bushing or cap |56 rests on the upper surface of the record,its upper end being bored to receive the end of the spindle which is oismaller diameter than the fiuted portion.

l groove |51 is here formed into which two metal balls |59 engage forthepurpose of securing a cap |59 to the end of the spindle, each ballbeing biased by a pin |60 secured to the lower end of a spring |6| whoseupper end is secured to the cap by a screw or rivet |62. Thisarrangement permits ready removal of the cap and a record from therecord spindle. The cap |56 has a conical shaped head |59 at its upperend, the point or apex of the cone serving as an indicator in connectionwith scale 66 (see Fig. 2) to indicate the position of matter recordedon the record. The recording device forms a spiral shaped sound track|63 in the record in a manner to be described.

It-ris not necessary to use the cap as a means of holding the record inplace. The center hole in the record is made small enough to cause therecord to be held by friction to the spindle 95. The cap, however,constitutes a convenient index member which can be readily removed tofacili- 'tate application and removal of records.

Recording and* reproducing units the stylus |65 of the recording unit 30(see Fig. 8 also). Wheel |64 is mountedl on the end of a shaft |66journalled for rotation in a bearing member |61 which is mounted forpivoted movement on a pin |66 carried by a lug |69 of bracket |05.Shaft|66 is recessed as shown to receive a pin formed on the end of ascrew |10, thus retaining the shaft in proper position axially. Member|61 is bored to receive an adjusting screw |1| which engages a threadedhole in a lug |12 projecting from the bracket |05. Cylindrical blocks ofsoft rubber |13 and |14 are arranged as shown, under compression, sothat upon adjustment of screw |1|, wheel |64'may be slightly adjusted inposition with reference to the stylus. The wheel |64 is formed ofalternate laminations |15 and |16 of soft rubber and steel respectivelyheld in place against a ange |66a by a screw |11 threaded into the endof shaft |66, the end of screw |11 being extended to form a head |11a oflarge diameter cooperating with the adjacent disc |16. A thrust ball|18- is seated in a recess formed in the end of the screw, and isretained in position by a spring |19 whose end is secured to lug |12 byscrew |80. The stylus may engage the record directlyover one of therubber laminations |15 to permit the sound track to be formed therein,the rubber permitting the lower surface as well as the uppersurfa'ceithe record to be deformed by the action of the stylus nwhichforms the sound track by its moving sidewise. Fig. 22 shows on anenlarged scale, depressions of the sound track in the upper surface of arecord and corresponding projections formed on its lower surface.

.As shown in Fig. 11, control shaft |35a passes through partition wall|09 and is journalled in the end walls |06 and |01 of bracket |05 ,andalso extends through a partition wallflBZ extending across the top ofthe casing. The end of this shaft carries a cam unit |09 (see Fig. 5also) which controls the positioning of the recorder 30 and reproducer29. The recorder 30 is supported for vertical movement by twosubstantially parallel arms |60 and |69 connected to it by screws |06and |6'|, the rear ends of these arms being pivotally supported byscrews and |89 threaded into a lug |06a extending from wall |82 (seeFigs. l5 and 16) and a lug |6911 on a bracket on the wall |02. Arm |80carries a roller |9015 which engages a cam |9| forming a part of camunit |99 and having a rise portion |92 which raises or lowersthe/recorder and a large dwell portion |93 which maintains it in itselevated or inoperative position. The parallel supporting links serve tomaintain the recorder unit in parallel position as it is raised orlowered.

The reproducer unit 29 is mounted for'both sidewise and vertical motionby its attachment to the end of a lever |90 having anoiset extension|95, the lever being pivoted loosely on a shoulder screw |96 threadedinto the inner end of another lever |91 which is in turn pivotallysupported for up-and down movements on a cylindrical extension |98 (Fig.15) formed on its -inner end, this extension engaging a bore made in anenlarged hub portion |99 formed on the end of a third lever 200. Avertical screw 20| passing through a bore formed in the hub |99 andthreaded into the iixed bracket |90 serves y as a pivotal support forsidewise motion of all three levers. A spring 203 (Fig. 17) having oneend xed to a pin 204e on hub portion |99 and its other end to a fixedpin 204 biases the levers toward the camunit |83. The levers |91 and 200

